Many types of reciprocating power tools are presently available. However, most such power tools, such as those disclosed in U.S. Pat. No. 6,705,409, include one handle opposite the end of the power tool to which the work piece is connected. This configuration is undesirable for several reasons. First, when the user's wrist, elbow, and/or shoulder are positioned at an extreme angle as the prior art orientations require, the force transferred to the user from the power tool is not evenly disbursed to the user. To properly position the work piece of the prior art power tool, the user's hand must be positioned in close proximity to the user's shoulder with the user's elbow positioned behind the user's chest. This position is similar to the position of those anatomical structures if the user were lying face down with the user's hands placed flat against the floor approximately shoulder-width apart.
If the user's wrist, elbow, and/or shoulder are positioned so that the user's wrist, elbow, and/or shoulder are at the limit of travel for the user's hand, nearly the entire force transferred from the power tool to the user's hand is subsequently transferred through the user's wrist, elbow, and shoulder to be dispersed by the user's body. When those anatomical structures are in the above-described position, the relevant tendons, ligaments, muscles, and other structures are substantially at the limit of travel and not able to absorb any further energy. Subsequently, when the entire force from the power tool 1 is transferred through those anatomical structures, the force will tend put an undue amount of stress onto those anatomical structures, often resulting in damage. The situation is analogous to placing an additional load on a spring that is already stretched to its limit; additional load either causes the spring to break or deforms and damages the spring so that it no longer performs properly. Placing the handles as shown in the prior art requires that the user bend the user's wrists, elbows, and shoulders to place the handle in close proximity to the user's chest to properly position the work piece and operate the power tool.
DETAILED DESCRIPTION - LISTING OF ELEMENTSELEMENT DESCRIPTIONELEMENT #Power Tool1Work Piece2First Handle3Second Handle4Tool Body5Tool Body First End6Tool Body Second End7Handle Distal End8Internal Portion9User10Throttle lever11Receiver Cup12Clutch Band13Exhaust Shield14Valve Seat15Valve16Washer17Top Valve Seat18Piston19Pneumatic Motor20Retainer21User's Hands22Barrel23First Air Passage24Second Air Passage25Tool Feed26Throttle Valve27Air Inlet28Cavity30Pneumatic Percussive Mechanism31Sight Line32Support Ring33
Before the various embodiments of the present invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that phraseology and terminology used herein with reference to device or element orientation (such as, for example, terms like “front”, “back”, “up”, “down”, “top”, “bottom”, and the like) are only used to simplify description of the present invention, and do not alone indicate or imply that the device or element referred to must have a particular orientation. In addition, terms such as “first”, “second”, and “third” are used herein and in the appended claims for purposes of description and are not intended to indicate or imply relative importance or significance.